Office of Compensation Analysis and Support 

Program Evaluation Plan

Document Number: OCAS-PEP-013 

Effective Date: 03/21/2007 

Revision No. 0

Evaluation of the Impact of Changes to the Isotopic Ratios in for the 

Paducah Gaseous Diffusion Plant Page 1 of 2 

Subject Expert: TBD 

Author: Signature on file Date: 03/21/2007 Dave Allen, HP Team Leader 

Approval: Signature on file Date: 03/21/2007 J.W. Neton, Associate Director for Science 

Supersedes: None 

RECORD OF ISSUE/REVISIONS 

ISSUE 

AUTHORIZATION 

DATE 

03/21/2007

EFFECTIVE 

DATE 

03/21/2007 

REV. NO. 

0 

DESCRIPTION 

This document provides a plan to evaluate 

the impact on previously completed Paducah 

dose reconstructions of utilizing newly 

developed isotopic ratios.

1.0 Description

October 25, 2006, Revision 01 of ORAUT-TKBS-0019-5, Occupational Internal Dose 

was issued as part of the biennial review process. During the biennial revision of this 

TBD section, the information provided in existing document was evaluated to ensure that 

the published isotopic ratios for transuranic (TRU) radionuclides meet the criteria of 

providing either an accurate or maximum dose estimate. The results of the evaluation 

indicated that the current ratios did not meet that goal. Information provided in existing 

references (particularly PACE and the University of Utah, 2000; BJC, 2000), as well as 

that found in a new reference was assessed with the result that new TRU isotopic ratios 

were developed and are included in the TBD as Tables 5-2 and 5-2a in the revised 

document. 

On November 7, 2006 Revision 01 of ORAUT-TKBS-0019-4, Occupational 

Environmental Dose was issued. A revaluation of the source data for ORAUT-TKBS0019-5 led to a revision to the TRU isotopic ratios (relative to uranium) for estimating 

dose from these radionuclides. In addition, the authors have been able to categorize these 

ratios according to specific processes and periods as described below in conjunction with 

ORAUT-TKBS-0019-5. 
Office of Compensation Analysis and Support

Document Number: OCAS-PEP-013 Program Evaluation Plan 

Effective Date: 03/21/2007 Revision No. 0 Page 2 of 2 

2.0 Issue Evaluation

The new isotopic ratios will provide a bounding, yet reasonable estimate of internal dose 

due to TRU radionuclides present in recycled uranium. The new data is categorized 

according to specific plant areas shown below for both pre-1983 and post-1983 

operations: 

Pulverizer, Ash Handling, Green Salt Production 

Converter Salvage Line 

99Tc/237Np Recovery 

Balance of Plant (cascade operations/maintenance, etc) 

In addition, ratios for 241Am and plutonium isotopes (238Pu, 240Pu, 242Pu, and 241Pu) were 

added. These changes will have the effect of increasing the dose estimates for claimants 

who worked in these operations from 1953 through the end of enrichment operations, 

with the exception of Balance of Plant Operations which will have lower dose estimates. 

The changes to the ratios were included in the latest revision to ORAUT-TKBS-0019-4, 

Environmental Dose since this information is key to estimating the dose to individuals 

exterior to the process buildings but potentially exposed to effluents. Overall, the revised 

ratios will increase the estimated dose to claimants exposed to effluents from the 

identified operation from 1953 through the end of enrichment operations, with the 

exception of Balance of Plant Operations which will have lower dose estimates. 

3.0 Plan for Resolution or Corrective Action

An initial selection of claims will be based on the following search criteria: 

1. Probability of Causation (POC) less than 50% 

2. Dose Reconstructions completed prior to November 7, 2006. 

The TBD requires the dose reconstuctor to determine in which area the individual 

worked. Those determined to have worked in the area designated as the balance of the 

plant, will not require further evaluation since the dose would be reduced. This results in 

the additional manual criteria. 

3. Determined to have worked in the “Balance of the plant”. 

Evaluation of the remaining claims will start with those having the highest original POC. 

As these claims are completed, it is possible that a point will be reach in which it is clear 

no additional claims will reach a POC of 50%. If this occurs, that point will be 

documented in the Program Evaluation Report and the remaining claims will not be 

evaluated. It is likely that this will require different points for the different “plant areas” 

and possibly other factors.